Relocation of older adults to nursing homes is an important issue for health care providers due to recent and projected increases in the acuity and numbers of nursing home residents. However, health status of older adults and numbers of following relocation to a nursing home has not been adequately addressed because previous studies have chiefly focused on long-stay residents' mortality 6 months to 1 year following relocation from one nursing home to another. This study will investigate short- and long-stay residents' stability of mental status, functional health, and mood over 7-day and 14-day periods immediately following admission to a nursing home; identify relationships between instrument scores and latent health status properties; develop instruments for screening stability of health status; and determine predictors of outcome at 1 and 3 months, and number of days in the nursing home using data obtained upon admission. A prospective design will be used, with interviews at Day 1, Day 7, and Day 14, and chart review at Month 1 and Month 3 following admission. Participants (N = 300), over age 60 and able to communicate in English, will be selected sequentially and interviewed as they are admitted to eight nursing homes. Mental status will be evaluated using Short Portable Mental Status Questionnaire; functional health using the Scaled Outcome Criteria and Health Self-Report; and mood using the Mood Adjective Checklist. Additional data will be obtained on expected length of stay, outcome, demographic, and control variables. Matched-pairs t-test orthogonal contrasts will determine health status stability during the first 7 and 14 days, and LISREL confirmatory factor analysis will be used to estimate relationships between instrument scores and latent health status properties. Step-wise multiple linear regression will be used to develop instruments for screening stability of health status and to specify prediction equations for outcome at Month 1, Month 3, and number of days in the nursing home. Results will identify short- and long-stay nursing home residents at risk for health status instability immediately following relocation; delineate parameters for resident assessment upon admission; and identify areas for future research, such as clinical intervention and cost effectiveness studies.